U.S. Pat. No. 6,273,771, which is hereby incorporated by reference herein, discloses a control system for a marine vessel that incorporates a marine propulsion system that can be attached to a marine vessel and connected in signal communication with a serial communication bus and a controller. A plurality of input devices and output devices are also connected in signal communication with the communication bus and a bus access manager, such as a CAN Kingdom network, is connected in signal communication with the controller to regulate the incorporation of additional devices to the plurality of devices in signal communication with the bus whereby the controller is connected in signal communication with each of the plurality of devices on the communication bus. The input and output devices can each transmit messages to the serial communication bus for receipt by other devices.
U.S. Pat. No. 7,305,928, which is hereby incorporated by reference herein, discloses a vessel positioning system that maneuvers a marine vessel in such a way that the vessel maintains its global position and heading in accordance with a desired position and heading selected by the operator of the marine vessel. When used in conjunction with a joystick, the operator of the marine vessel can place the system in a station keeping enabled mode and the system then maintains the desired position obtained upon the initial change in the joystick from an active mode to an inactive mode. In this way, the operator can selectively maneuver the marine vessel manually and, when the joystick is released, the vessel will maintain the position in which it was at the instant the operator stopped maneuvering it with the joystick.
U.S. Pat. No. 8,478,464, which is hereby incorporated by reference herein, discloses systems and methods for orienting a marine vessel to enhance available thrust in a station keeping mode. A control device having a memory and a programmable circuit is programmed to control operation of a plurality of marine propulsion devices to maintain orientation of a marine vessel in a selected global position. The control device is programmed to calculate a direction of a resultant thrust vector associated with the plurality of marine propulsion devices that is necessary to maintain the vessel in the selected global position. The control device is programmed to control operation of the plurality of marine propulsion devices to change the actual heading of the marine vessel to align the actual heading with the thrust vector.
Unpublished U.S. patent application Ser. No. 15/425,184, filed Feb. 6, 2017, which is incorporated by reference herein, discloses a method for maintaining a marine vessel propelled by a marine propulsion device in a selected position, including determining a current global position of the marine vessel and receiving a signal command to maintain the current global position. The current global position is stored as a target global position in response to receiving the signal command. A subsequent global position of the marine vessel is determined and a position error difference between the subsequent global position and the target global position is determined. The method includes determining marine vessel movements required to minimize the position error difference, and causing the marine propulsion device to produce a thrust having a magnitude, a direction, and an angle calculated to result in achievement of the required marine vessel movements. At least one of timing and frequency of discontinuity of thrust production is controlled while the position error difference is minimized.
Other patents describing various station keeping features and related system and method improvements include: U.S. Pat. Nos. 7,267,068; 8,050,630; 8,417,399; 8,694,248; 8,807,059; 8,924,054; 9,132,903; 9,377,780; 9,733,645; and unpublished U.S. patent application Ser. No. 14/807,217, filed Jul. 23, 2015. Each of these patents and applications is hereby incorporated by reference herein.